Brake Light Switch: Description and Operation

Stop (brake) lamp switch





The stop (brake) lamp switch is a single pole switch positioned at the brake pedal lever. The stop (brake) lamp switch self-adjusts during installation.

The Brake Control Module (BCM) receives information about the status of the stop (brake) lamp switch via the Engine Control Module (ECM). The stop (brake) lamp switch signal is used by the Brake Control Module (BCM) to diagnose faults in the pedal position sensor. The stop (brake) lamp switch is supplied with power from the battery. When the switch is closed, the signal is grounded through the Engine Control Module (ECM). The Engine Control Module (ECM) then transmits a signal on the Control Area Network (CAN) indicating that the stop (brake) lamp switch has been activated. There are diagnostics for the stop (brake) lamp switch.